Timing mechanism



Jan. 27, 1942. l. E. MccABE 2,270,952

' TIMING MEcHANIsM original Filed Feb.` 27, 1939 2 s1wes-sma1a 1 'PE l 44 4s INVNTOR /H E. M: C1985 ATTORNEY,

Jan. 27, 1942.

l. E. MCCABE TIMING MECHANISM 2 Sheets-Sheet 2 Original Filed Feb. 27, 1939 y BY ATTORNEY.

" by the remote control.

Patented Jan. 27, 1942 258,591. Divided and this application May 25, 19410, Serial No. 337,154

2 Claims.

This invention relates to improvements in timing mechanisms for operating an electric switch, and this application is a division of this applicants prior co-pending application Serial No.v

258,591, led February 27, 1939. i Said parent application, Serial No. 258,591, discloses an electro-'thermal motor for actuating a timer mechanism to operate an electric switch normally opened and closed by a remote control, such as disclosed in this applicants prior Patent (c1. iisg-315) tively, said brackets mounted upon the upper portion of a base plate B so that the centers of the respective cylindrical sections lie in the same horizontal plane with their respective adjacent peripheries spaced apart from eachother. A floating operating link 5 is provided with an up ward projection 6 at one end terminating in an angular extension liwhich is passed through a slot provided therefor inthe free end of the cy- No. 2,139,454, December 6, 1938, and a combination of 4these two devices in such a manner that the timer mechanism is rendered operative only during those periods when the switch is opened This combination produces an improved timing mechanism and is the subject matter of this divisional application.

It is an object of this invention to provide an electro-thermal motor in connection with a timer mechanism to open and close. an electric switch,

both of which are actuated by a remote control in such a manner that while the switch is opened by the remote control the electro-thermal motor will be rendered operative to alternately close and open the switch independently ofthe remote control.

With these and other objects in view, reference is made to the accompanying sheets of drawings which illustrate a preferred form of this invention, with the understanding that detail changes may be made without departing from the scope thereof. Y

In the drawings: e

Figure 1 is a view in front elevation of aheat motor constructed in accordance with this invention, with parts broken away and detached from the base or supporting plate.

Figure 2 is a view in side elevation of Figure 1 looking upon the lefthand side thereof.

, Figure 3 is a view in side elevation of Figure 1 looking upon the right side.

Figure 4 is atop plan view of the driving mech.- anism with parts broken awa;- and partly in section.

Figure 5 is a fragmentary detail view in elevation of the electrical resistance heating element.

Figure 6 is a View in front elevation of a practical application of this improved heat motor.

Figure 7 is a wiring diagram of Figure A6.

In the embodiment of this invention. as'illustrated in Figures 1, 2 and 3, cylindrical sections I and 2 of .bi-metallic metal are each provided with a re-entrant portion at one end, each of which is mounted upon oppositely disposed anlindrical section I and the opposite end of the link 5 is provided with an upward projection 8 adapted to be connected by a hinge 9 to the free end of the cylindrical section 2. The two projections 'l and 8 are so connected and arranged as to support the link 5 in a horizontal position. The link 5 is provided with a depending portion I0 extending below the projection 8, the lower v extremity of which supports a heater actuator I I pivoted at one end to the portion I0. The free end of the actuator II mounts a roller I2 and is normally urged in an upward direction by the spring I3, one end of which engages the actuator II with the other end anchored upon the portion I0 ofthe link 5. The roller I2 co-acts with an oscillator I4 carried upon an enlarged portion I5 of a shaft I6 mounted in a bearing therefor in the back plate B. An oscillating heater support plate I'I of insulating material is secured to the enlarged portion I5, which plate is provided with terminal posts I8 and I9 upon the upper side thereof. A flat rectangular electric resistance heater 20 with its flat surface positioned parallel to the surfaces of the cylindrical sections I and 2 is supported between the adjacent surfaces thereof by electrical'conductors 2| and 22 connected to the opposite ends of the resistance wire 23 of the heater 20. The electrical conductors are preferably covered with insulation and their lower respective ends are connected to the terminal posts I8 and I9 upon the insulated heater actuator plate I1.

The outer end of the shaft I6 is mounted in a bearing therefor in a horizontal front plate 24 spaced apart from the base plate B by studs 25 to lie parallel therewith, as shown in Figures 2 and 3,'so that the shaft I6 may be oscillated in the said bearings.

The oscillator I4 is kpreferably in the form of a threaded pin 26 terminating in a conical end received in the enlarged portion l5 of the shaft I6 to provide for adjustment. The upper end of the pin 26 is provided with-a knurled head 21 adapted to be engaged-and locked in the adjusted I position by the free end of a spring 28 secured'4 gular end portions of brackets' 3 and 4, respec- 5" to the outer end of the enlarged portionl I5 of the shaft I6. The lower conical end of the actuator I4 is adjusted so that the roller I2 of the actuator I I will normally engage one conical sur face thereof and oscillate the shaft I6 and plate I1 to cause the heater 20 to engage the adjacent surface of one of the cylindrical loi-metallic sections of the thermal members. The terminal posts I3 and I5 pass through the plate Il of insulating material and are connected to a source of electricity by conductors 29. When the current passes from the source through connectors 29, terminal posts IB and I8, conductors 2| and 22 and resistance wire 23 of the heater 2U, and the heater is in the position shown in Figure 1, it will cause the adjacent cylindrical section I of the thermal member to reduce in cylindrical form, thus moving the free end downwardly and inwardly, which will cause the floating lever 5 to be rotated about its hinge connection 9 with the other thermal member 2 and thereby cause the heat actuator I I to move toward the right causing the roller I2 to travel down the conical termination of the oscillator pin 26 to ride over the apex thereof. The tension of the spring I3 as the roller rides over the apex will cause the roller to travel upwardly over the opposite conical side of the pin 26 which will impart a rotation to the shaft I6 causing the heater support plate II to oscillate the heater 20 and bring it into contact with the thermal member 2. When the heater 20 contacts the adjacent surface of the thermal member 2, the thermal member 2 will be heated to impart a reverse movement to the floating link to cause the actuator II to travel in the opposite direction over the conical surface and apex of the oscillator I4 to impart a reverse oscillation to the heater 20. With the alternate heating of the thermal members one member when heated will be assisted by the other member while cooling whereby the combined moving force of both elements is applied to the floating lever 5 in moving it and an oscillating movement will be imparted to the heater 20 through the reciprocal movement of the floating link 5 as long as the resistance element 23 of the heater 20 is energized.

The floating link 5 is provided with two spaced apart depending similar operating members 30 and 3l adapted to receive in sliding engagement between them a stud 32 carried upon a reciprocating cradle 33. The opposite ends of the cradle 33 are pivotally mounted upon shafts 34 and 35, each of which shafts are supported by a pair of links 35 and 31, the lower ends of which are piv otally mounted upon studs 38 and 39, mounted between the base plate B and front plate 24; each pair of links being connected intermediate their length by spacing members 4I). By this construction, when the oscillating heater causes the thermal members I and 2 to impart an oscillating movement to the floating link 5, this movement through the operating members 20 and 3| will transmit a reciprocating movement to the cradle 33.

' A shaft 4I is received within a hub, mounted upon a ratchet wheel 43 in any desired manner to be rotatable therewith. The ratchet wheel 43 is located between the base plate B and cradle 33 with the hub passing through a bearing 42 provided therefor in the base plate. The reciproeating movement of the cradle 33 is transmitted to the ratchet wheel 43 to impart a rotation to the shaft 4I by pawls 44 in the form of flat springs each having slots 45 adjacent their free i end adapted to cause the body of the spring ad- 4 base plate B2.

jacent the free end to form a pawl to engage the ratchet teeth of the ratchet wheel 43 on opposite sides of the shaft 4I. The end oi the upper spring pawl 44 opposite the slot 45 is secured to the upper end of a portion 45 of the cradle 33 extending upwardly therefrom above the pivot 35 and the corresponding portion of the lower spring pawl 44 is secured to a portion 4l' of the pawl 33 depending below the pivot 34 and cut out to provide clearance for the spacer 40.

By this arrangement, the pawls 44 are always in engagement with the teeth of the ratchet wheel 43. Movement of the cradle to the right imparts a clockwise rotation to the ratchet wheel by the upper pawl 44 while movement of the cradle 33 to the left continues the clockwise rotation of the ratchet Wheel by the movement of thelowerpawl 44. While one pawl imparts movement to the ratchet wheel the other pawl travels over the ratchet teeth.

By providing the ratchet wheel 43 with fine teeth and synchronizing the movement of the elements I and 2, a continuous or substantially continuous rotation may be imparted to the shaft 4I. In order to synchronize the movements of the free ends of the elements I and 2, it is preferable to provide an vadjustment for one of the elements. As shown in Figure 1, the bracket 4 is made adjustable so that the thermal element 2 may be adjusted in a vertical direction. The bracket 4 is provided with a right angular extension 48 which receives an adjusting screw 49 mounted in a bracket 5U secured to the base plate B. The bracket 4 is also provided with a vertical slot through which a clamp screw 5I passes and by means of which the bracket may be secured in position after adjustment. Should the move ment of the two thermal elements differ slightly when heated, the element 2 may be raised or lowered to adjust the relationship of the heater actuator roller I2 to the oscillator I4 for each element. Therefore, the heating effect of the heater on each element may be timed to cause each element, when heated, to apply the same degree of rotation to the ratchet wheel 43 and since the oscillator I4 is adjustable the heating periods may be determined to regulate the vnumber of degree rotation which may be imparted by the thermal members for each cycle of operation thus providing a certain desired rotation of the wheel 43 over a desired period of time.

' Figure 6 is an illustration of a practical application of the heat motor disclosed in Figures l to 5, inclusive; Figure 7 is a wiring diagram of the apparatus shown in Figure 6. The apparatus shown in Figure 6 is a timer mechanism disclosed in detail in this applicant's prior Patent No. 2,139,454, granted December 6, 1938. This mechanism is designed particularly as a timing device for use in connection with other devices for controlling the operation of an electrically operated and controlled coal stoking mechanism for domestic and industrial plants. In Figure 6, the mechanism is shown mounted upon a panel 52, and the timing mechanism is enclosed in a casing 53 mounted upon a base plate B2, which corresponds to the base plate B of the heat motor hereinbefore described, and is spaced apart from the panel 52. In the abovesaid Letters Patent. rotation was imparted to the operating shaft of the timing mechanism by a self-starting synchronous motor mounted upon the back of the In this application of the heat motor heretofore described and illustrated in Figures 1 to 5, inclusive, the shaft 4I corre- -to binding posth 55.

spends to the operating shaft of the timing mechanism. In the wiring diagram shown in Figure '1, the mechanism mounted on .the panel 52 is shown as applied to the control of a stoker motor in which the commercial line is indicated to one side of a stationary primary coil PC of a` repulsion type relay R, the other side of which is connected through binding post 51 and thence The windings of the secondary coil SC of the relay R are connected to binding posts 58 and 59 which in turn are connected to a room thermostat T. A motor switch MS operated by the relay, normally open when the relay is de-energized, is connected to binding posts 54- and 56, the latter serving also as a terminal ior one connection to a motor M. The other connection from the motor M is connected to binding post 51. When the secondary circuit is open through the room thermostat T, the secondary coil SC is de-energized and falls to rest upon the top of the primary coil PC. When the room thermostat closes the secondary circuit, the secondary coil is energized and is repelled to float above the primary coil PC. This floating movement is employed to close the motor switch MS so that when the motor switch is closed, the current will pass from binding post 54 through the motor switch, binding post 56 through the stoker motor M to the binding post 51 and froml this point to binding post 55.

The timing mechanism mounted in the casing 53 includes a cam assembly 60 rotated by the shaft 4I; a cam lever 6i mounting a pin 62 to ride over the surfaces of the cam 60 under tension of the spring 63; and an actuating lever 64 pivotally mounted upon the cam lever vv6| so arl ranged as to be moved about its pivot as the cam lever 6i drops into a notched portion of the cam 60 to cooperate with a strip 65 extending from the upper surface of the secondary coil SC ofthe relay, whereby when the actuating lever 6'4 is swung to the left,- it causes the secondary coil to rotate upwardly about the pivot 66 to close the motor switch MS, as shown in Figure 6. The end of a lever 61 is illustrated for positioning parts ,of the timing mechanism, not shown, to determine the duration of time the lever 64 may hold the motor switch closed, as disclosed in said Patent No. 2,139,454.

In the timer mechanism illustrated and ldescribed in said Patent No. 2,139,454, a constantly energized self-starting synchronous electric motor is employed to operate'the timer mechanism.

The timing mechanism is designed for the purpose of controlling theoperation of a motor operated stoker, to supply coal at periodic intervals,

to maintain the fire during the time the room thermostat is not calling for heat.

This invention contemplates. the application of the 'electrically actuated heat or electro-thermal motor, disclosed herein, to a motor operated timing device of the type disclosed in the aforesaid patent in such a manner that only during y those periods when the thermostat is not calling ,t for heat from the thermostat will operate the relay to close the motor switch and render the electro-thermal motor inoperative as long as `the thermostat circuit remains closed. When the electrically actuated heat or electro-thermal motor, as above described, is connected in circuit with the mechanism illustrated in Figure 6, in the manner shown in the wiring diagram of Figure '1, it is seen that the heating element 23 is always connected through terminal posts I8 and I9 and conductors 29 to binding posts 58 and 59 so that when the room thermostat T is open, or not calling for heat, the heater 23 will be in circuit with the windings of the secondary coil SC and as the primary coil PC is always connected in circuit with the source of electricity a current will be induced in the secondary coil which, when the room thermostat is closed, normally repels the secondary coil to close the motor switch MS. In this application of the electro-thermal motor the electrical resistance 23 is designed so that the heater interposes suiiicient resistance in the circuit of the secondary coil, when the room thermostat is open, to prevent the repulsion of the secondary coil and thereby when the room thermostat is open the electric vheat motor willr be operated to actuate the timing mechanism. When the room thermostat closes its circuit through binding posts 58 and 59 to the secondary coil it will short-circuit the electro-thermal motor and render the same inoperative and thus preserve the resistance heater 23 by limiting its operation to those periods when the circuit to the room thermostat is open. practice, a boiler control BC is interposed in the line L, as shown in Figure '1, to prevent operation of the stoker when conditions within the boiler do not warrant it.

Whilev this application of the heat or electrothermal motor is described in connection with the timing mechanism disclosed in said Patent No. 2,1392454 as applied to an electrically operated and' controlled stoker mechanism, it is obvious that the heat motor ,may be similarly operated by remote control other than a room thermostat and the opening and closing of the motor switch may be employed to control the operation of a motor for purposes other than the operation of a coal stoker mechanism.

What I claim is:

1. In a circuit controller, an electric switch in the circuit to be controlled, electrical means `for operating said switch comprising a coil movable over ametal core, a circuit including said movable coil, a stationary coil mounted upon the core adapted to be connected in circuit to a source of electricity to induce a low voltage circuit in the movable coil and repel said coil when the circuit through the movable coil is closed, means operating the electric switch in response to the movement of the movable coil; a control device in the movable coil circuit in combination with means to mechanically actuate the movable coil, timing mechanism for periodically actuating the mechanical means, a thermal-electro heat motor for operating the timing mechanism having an electrical resistance heating element connected in the movable coil circuit in parallel to the control device, said heating element, when the control device is in open circuit position, energized' to operate the heat motor, said heating element limiting the current ilow through the movable coil to prevent the electrical repulsion thereof, said heating element being shunted and rendered inoperative upon the closure of the control de- As in commonl vice circuit to cause the electrical repulsion of the movable coil.

2. In a circuit controller, an electric switch in the circuit to be controlled, electrical means for operating said switch comprising a coil movable over a metal core, a circuit including said movable coil, a stationary coil mounted upon the core adapted to be connected in circuit to a source of electricity to induce a low voltage circuit in the movable coil and repel said coil when the circuit through the movable coil is closed, means operating the electric switch in response to the movement of the movable coil, a control device in the movable coil circuit in combination with means to mechanically actuate the movable coil, timing mechanism for periodically actuating the mechanical meansl a thermal-electro heat motor for operating the timing mechanism including two spaced apart coils of thermal metal each having one end thereof fixed, a movable electrical resistance heating element arranged between the coils mounted to heat alternately the respective coils, an operating shaft connected to the timing mechanism, transmission means for transmitting the movement of the free ends oi the thermal elements to the shaft and additional means actuated oy said transmission means for moving the heating element, said element connected in the movable coil circuit in parallel to the control device to be energized when the control device is in open circuit position, said heating element limiting the current ow through the movable coil to prevent the electrical repulsion thereof, said heating element being shunted and rendered inoperative upon the closure of the control device circuit to cause the electrical repulsion of the movable coil.

IRA E. MCCABE. 

